Use of 12-lead electrocardiography for prediction of left main coronary artery significant lesion

ABSTRACT

Significant Left Main Coronary Artery [LMCA] lesion [>/= 50% stenosis] is rare and most of these patients die of sudden death or cardiogenic shock. Therefbre, prediction of LMCA obstruction by electrocardiography [ECG] is important to identity these cases. Concerning the risk of LMCA lesions early diagnosis of these lesions with ECG causes earlier and better management. From December 2005 to December 2006, ECG findings of 51 patients with LMCA significant lesion [LMCA group] were compared with 492 patients will] normal coronary angiography [control group]. Nine patients of LMCA group and 18 controls had signs of anterior myocardial infarction [Ml]. ST elevation [>/= 1.0 mV] in two consecutive precordial leads or pathological Q wave, in ECG that was taken in 48 hours before performing coronary angiography. Chi-Square Test was used to compare ECG findings in these groups. Inverted U wave [Biphasic T wave in V1 to V4 was seen more [77.8%] in LMCA group with signs of anterior MI [than controls with signs of anterior MI 133.3%] [p < 0.046] and more in LMCA group without signs of anterior MI [19.0%] than in controls without signs of anterior MI [7.4%] [p<0.009]. ST elevation in aVR [>/= 0.5 mm] was useful for differentiating of LMCA group without signs of anterior MI [42.9%] from control group without signs of anterior MI [20.5%] [p<0.001] but not for differentiating these groups with signs of anterior MI. [p<0.121] ST depression in interior lards was not a predictor of LMCA obstruction due to p<0.221 and 0.471 for LMCA group without signs of anterior MI and LMCA group with signs of anterior MI, respectively. In patients with ECG features of anterior myocardial infarction, Inverted U wave [Biphasic T wave] in V1 to V4 is the only ECG finding in favor of LMCA obstruction, [sensitivity 77.8%] ST elevation in aVR. with low sensitivity [42.9%]. is a predictor of LMCA significant lesion in patients with chronic angina pectoris